Compost is largely decayed organic matter which is utilized as a fertilizer for soil. It is formed by bacterial digestion of lawn cuttings, tree cuttings, ground Christmas trees, farm and garden waste, unsalable produce and the like. The cuttings may be of any size and may be ground at the time a compost pile is formed.
The pile of cuttings, which may be termed "green waste," is allowed to stand in a moist condition as bacterial action causes decay and eventually turns brown.
Sources for compost include yard clippings, which are typically bagged in plastic bags, unsalable produce such as fruits and vegetables which are also contained in plastic bags, and find their way, bagged, to garbage dumps. As the contents for forming compost must normally be reduced in size to facilitate the decaying operation, it is convenient to reduce the size of the raw materials while in their bags. This develops film fragments.
The green waste is usually ground to a size that will pass through a six to eight inch (6-8") screen. Plastic bags will usually shred to strips of 12" or more in length and occupy about one to two percent (1-2%) by weight of the green waste. In any operation of separating mature or stable compost into fractions of desired size from oversize, the plastic will concentrate in the oversize and also tend to clog screens used for sizing of the compost.
Since the oversize has the utility of being combinable with fresh green waste to generate the new compost, it is desirable to eliminate the shredded plastic film from the compost at some stage in its processing.
This is the subject of the instant invention.